California White Sturgeon are a long-lived, slow growing, and late-reproducing fish species common to estuaries and coastal habitats along the West Coast of North America. These life history characteristics make their population exceptionally vulnerable to habitat loss, degradation, and over exploitation. In addition, this also makes it challenging to study and manage their population effectively. Various studies involving electronic tagging, video monitoring, trapping and recreational catch efforts have provided insights into migratory patterns and spatial distributions of White Sturgeon in the Sacramento-San Joaquin River system. However, these methods can provide only a brief snapshot in time. In contrast, trace element and isotope analysis of calcified sturgeon fin rays using laser ablation is a non-lethal sampling method capable of reconstructing freshwater/marine residence and migratory patterns throughout an individual’s lifespan. To better understand White Sturgeon life history strategies and the inter-annual variability with response to water year, we used laser ablation mass spectrometry to measure strontium isotope ratios in fin rays from wild sturgeon and found that many fish spent their lives primarily in estuarine environments, with very little evidence of freshwater residence within the first year. We also conducted an experiment focusing on early fin ray calcification to determine how early fin ray microchemistry begins to record migration patterns using trace elements. We found that fin rays begin calcifying and incorporating trace elements from the water as early 30 days post hatch or 30 mm total length and are nearly 95% calcified by 70 mm total length or 72 days post hatch. Results of these studies provide new insights into the movement patterns of White Sturgeon in the Sacramento-San Joaquin River system which can help resource managers refine flow management and habitat restoration strategies to optimize potential impact to sturgeon.